The use of electric belly-band heaters is well known in the prior art. Typically, these heaters use resistance heating wherein a resistance heating wire is encased in a metal sheath. The metal sheath is in contact with the item or material to be heated. One type of belly-band heater (commonly referred to as a “crankcase heater”, “compressor heater” or “sump heater”) is used to heat refrigeration compressors or air-conditioning compressors. The heater employs a standard hose clamp for attachment to the compressor. The standard hose clamp is cut in two pieces with each piece affixed (welded for example) to opposite ends of the heater's metal sheath. Assembly of the heater to the compressor is accomplished by engaging the two ends of the clamp as intended and then tightening the assembly around the selected compressor location. This type of heater construction can also be used for heating containers such as barrels, heating pipes, etc.
The belly-band heater has an insulated electric lead wire exiting each end of the metal sheath. A frequent requirement in the use of these heaters is for the lead wires to be routed in standard metal conduit. Further, it is often required that the conduit enclose the lead wires from the point where each lead exits the heater sheath to where the lead wires enter an electrical junction box or boxes.
FIG. 1 shows a typical electric belly-band heater designated by the reference numeral 10 and including the hose clamp pieces 1 and 3, and the screw mechanism 5. A metal sheath 7 extends between the two pieces 1 and 3, with the hose pieces attached to the sheath by welding or the like. The metal sheath 7 encases an electrically insulated resistance heating wire 9 and includes a fluted strip portion 8, which interfaces with the equipment or material requiring heating. The wire 9 exits the metal sheath 7 as a pair of lead wire ends 11 for encasing in conduit and/or connection to the appropriate electrical power source and controls.
Presently, the requirement of encasing the lead wires in conduit is achieved by attaching specialized parts/items where the heater is being used so as to protect the lead wires and meet installation codes. This procedure is both time-consuming and costly. In conjunction with the special rigging required to meet the requirement of enclosing the lead wires at the heater itself, opposite ends of the conduit would also be attached to standard junction boxes or the like.
In light of the difficulties in enclosing the lead wires emanating from an electric belly-band heater, a need exists for improvements in this area to reduce costs and time of installation. The present invention solves this need by providing an improved electric belly-band heater, wherein the heater utilizes a conduit fitting housing made as part of the heater itself. Once the heater is installed at a desired location, the appropriate conduit fittings and conduit can easily be connected to the heater to encase the lead wires, thus avoiding the need for any special rigging or costly modifications.